This menu allows you save or rename the map project, and also save individual maps layers in the project (eg. texture).
This menu allows you to reload the whole map project, or any individual map layer in the project (eg. light map, texture, etc). This could be useful if you have made a mistake and wish to revert to the saved version.
This menu allows you to free up memory by closing individual maps in project. These maps can be re-loaded when you need them using the 'FileāLoad' menu (assuming the map had been saved).